Method of selectively positioning relay contacts



Aug. 15, 1961 G. R. BATES 2,995,812

METHOD OF SELECTIVELY POSITIONING RELAY CONTACTS Filed Dec. 4, 1957United States Patent 2,995,812 METHOD OF SELECTIVELY POSITIONING RELAYCONTACTS George R. Bates, Hinsdale, 111., assignor to Western ElectricCompany, Incorporated, New York, N.Y., a corporation of New York FiledDec. 4, 1957, Ser. No. 700,675 3 Claims. (Cl. 29-404) This inventionrelates to a method of using relay contact positioning tools havingcammed surfaces and more particularly to a method of stacking a numberof said tools to hold different patterns of relay contacts open duringoperation of the relay.

In testing a relay having covered banks of contacts, it is quite oftennecessary to remove the cover and thus expose the contacts to impuritiesof the surrounding air. Due to the delicate nature of relay contacts,testing tools must be able to engage, move and hold the contacts withoutdamage thereto.

Also, in positioning relay contacts for test purposes, it is highlydesirable to prevent any actual physical contact between the tool usedto open the relay contacts and the conducting surfaces of the contacts.Any insertion of a tool between the conducting surfaces of the relaycontacts enhances the chance of inducing impurities between the engagedsurfaces which may result in sticking of the contacts.

An object of the invention resides in a method of stacking cam facedtools to establish a preconcerted configuration of cam surfaces andutilizing the stacked tools to selectively position a bank of relaycontacts.

With this object in view, the present invention contemplates insertingtools in groups through a slot in a transparent relay contact cover. Thetools have cam portions on the sides thereof in predetermined patternsto open and position relay contacts.

The tools are used in combination with one another to provide variedpatterns of cam surfaces to open any desired combinations of relaycontacts of a given relay bank. The tools are insertable to any depthand are constructed thin enough to provide the insertion of the tools instacked relation. The transparent relay cover has slots therein whichallow for insertion and visible checking of the position of the toolswith respect to the relay contacts.

Other objects and advantages of the present invention, will be apparentfrom the following detailed description when considered in conjunctionwith the accompanying drawings, wherein:

FIGS. 1 and 2 are perspective views of tools having different camarrangements formed therein for carrying out the principles of thepresent invention;

FIG. 3 is a sectional view of a relay contact cover showing a typicaltool inserted through the cover and into a closed relay bank with onepair of contacts thereof cammed open by the tool;

FIG. 4 is a sectional View of a relay contact cover showing two tools instacked relation inserted through the relay contact cover and into aclosed relay bank to open two pairs of contacts of the relay bank;

FIG. 5 is a sectional View along line 5-5 of FIG. 3 showing the toolinserted in a closed relay bank to open a pair of contacts thereof; and

FIG. 6 is a cross-sectional view along line 66 of FIG. 4 showing twotypical tools inserted through the relay contact cover and into a closedcontact bank opening selected contacts thereof.

Referring to FIGS. 36, there is shown a portion of a relay having twobanks of relay contacts 2024 and 2529. A transparent cover 35 having twooppositely disposed slots 36 is placed over the relay contacts and issecured to the relay. The transparent cover acts to protect the relaycontacts from exposure to the surrounding atmosphere. A row ofstationary contacts 31 are positioned between the two banks of movablerelay contacts. A card 30 made of suitable dielectric material is placedbetween the stationary contacts 31 and the movable contacts 2029.Armature 33 operated by the relay windings (not shown) and positionedwithin the openings 32 of card 30 move the card from left to right toalternately open and close the relay banks 2024, 25-29.

Referring to FIG. 1, there is shown a tool 40 for carrying out thepresent invention made of any suitable resilient dielectric material. Abody 41 of the tool has a tapered or wedge-shaped end 42 and cam 43projecting from one side of the body 41. Tool 40 (FIGS. 3 and 5) isinserted through either slot 36 in the transparent cover 35. The tool 40is moved between the closed relay bank 2024 and the supports 34 for thestationary contacts 31. The cam 43 on the tool 40 moves a pair of relaycontacts 23 from the closed position to the position indicated withoutany contact of the tool with the abutting surfaces of the relaycontacts.

In FIG. 2, there is shown another tool 50 made of suitable dielectricmaterial having a body 51 and tapered ends 52. The body 51, as shown,has earns 53 and 54 projecting from the side thereof. One cam 54 extendsalong the body 51, a distance equal to or greater than the distancebetween two pair of relay contacts and the other cam 53 is smaller so asto only span a distance suflicient to engage one pair of contacts at atime.

Referring to FIGS. 4 and 6, card 30 has been moved to the left byarmature 33. The card in this position opens relay bank 2024 and closesrelay bank 25-29. Tool 40 is inserted through a slot 36 of thetransparent relay cover 35 and is moved between the closed relay contactbank 2529 and the supports 34 of the stationary contacts 31. Cam 43 ofthe tool 40 causes the contacts 26 to move away from the associatedstationary contact 31. An additional tool 50 is then inserted in stackedrelation to tool 40 and in the same manner as tool 40 to open pairs ofcontacts 28, 27 and 25. Contacts 27 and 28 are opened by the elongatedsingle cam 54 and contacts 25 are opened by the other smaller cam 53.The tools 40 and 50 could be placed in stacked relationship prior toinsertion in the slot 36 and more than two tools could be utilized toobtain other patterns of selectively opened contacts. The tools 40 and50 also may be moved relative to each other to vary the pattern ofcontacts to be opened for testing.

It is to be understood that there are alterations that can be made inarrangement and shape of the cams 43, 53 and 54 and that a multiplicityof tools 40' can be used in stacked relation to obtain any desiredpattern of opened and closed contacts in the relay contact bank.Further, it is to be understood that one tool 40 could be insertedthrough one slot 36 and a second tool could be inserted through theoppositely disposed slot to obtain a selected positioning of the relaycontacts.

It is to be understood that the above-described arrangements ofapparatus and construction of elemental parts are simply illustrative ofan application of the principles of the invention and many othermodifications may be made without departing from the invention.

What is claimed is:

1. A method of selectively positioning a bank of relay contacts inaccordance with a predetermined pattern which comprises, inserting atool having a cam surface on the side thereof so as to engagepredetermined contacts at points other than their abutting surfaces andthereby open said contacts, and then successively inserting additionaltools in juxtaposition of the first tool so as to engage additionalcontacts at points other than their abutting surfaces and thereby openfurther contacts to establish said predetermined pattern.

2. A method for selectively positioning relay contacts, comprisinginserting a first tool having a predetermined configuration into a relaybank to engage predetermined contacts thereof at points other than theirabutting surfaces to thereby open said contacts, inserting an additionalsimilar tool in juxtaposition of the first tool to engage otherpredetermined contacts of the relay at points other than their abuttingsurfaces to thereby open said other contacts, and moving the toolsWithin the relay bank to selectively change the pattern of contacts tobe opened.

3. The method of selectively positioning a plurality of relay contactsin a predetermined pattern in a relay bank, which method comprisesinserting a tool having a cam surface on one side thereof into the relaybank to engage predetermined contacts at points other than theircontacting surfaces and thereby to position the predetermined contactsout of their normal position, inserting another tool having a camsurface on one side thereof into the relay bank in juxtaposition to thefirst tool to engage other predetermined contacts at points other thantheir contacting surfaces and thereby to position said otherpredetermined contacts out of their normal position, and then moving thetools independently of each other Within the relay bank to selectivelyengage different contacts and thereby to change the pattern of thecontacts which are positioned by the tools.

References Cited in the file of this patent UNITED STATES PATENTS1,171,320 Chroninger Feb. 8, 1916 1,876,021 Quigley Sept. 6, 19321,985,531 Swenson Dec. 25, 1934 2,328,433 Dyer Aug. 31, 1943 2,398,564Stoner Apr. 16, 1946 2,714,304 Dedda Aug. 2, 1955 2,848,798 Davis Aug.26, 1958

